Method of and apparatus for removing surface moisture from rollable fresh whole fruit



May 23, 1939- H. PAxToN Er AL 2,159,047

` METHOD OF AND APPARTUS FOR RBIOVING SURFACE MOISTURE FROM ROLLABLE vFRESH 'HOLE FRUIT Filed March l, 1958 3 Sheets-Sheet l Q Tr May 23, 1939. H. PAxToN er AL METHOD OF AND APPARATUS FOR REIOVING SURFACE MOISTURE FROI ROLLABLE FRESH WHOLE FRUIT Filed March l, 1938 3 Sheets-Sheet 3 www May 23, H, PAXTON ET AL METHOD OF AND APPARATUS FOR REIOVING SURFACE MOISTURE FRQI ROLLABLE FRESH WHOLE FRUIT Flled arch ll 1938 3 Sheets-Sheet 2 Patented May 23, v1939 U METHOD OF AND APPARATUS FOR REMO'V-M ING SURFACE MOISTUREr FROM ROLL- ABLE FRESH'WIIOLE FRUIT Hale Paxton and Gerald C. Paxton, Santa Ana Calif., assis-nots to Food Machinery Corpora.-

tion, San Jose, Calif., a corporation of Delaapplication March 1, 193s, serial No. 193,303

. 7 Claims.

This invention vrelates to the art of commercially treating rollable fresh whole fruits in the process of preparing these for commercial shipment.

`It is an` object of this invention to provide a novel method and apparatus having substantially the same purpose yet embodying improvements over the Method of and apparatus for removing free water adhering to the outer surfaces of whole fresh fruit, disclosed in our copending application Ser. No. 61,182,1t1led January 28, 1936.

It is another object of this invention to provide a method and apparatus `as aforesaid which is economical in the use of heat and is susceptible of ready control to adapt it4 to varying atmospheric conditions.

kIt is another object of our invention toprovide an improved apparatus for removing surface 20 moisture from rollable fresh whole fruit which is n simple and compact in construction.

It is yet another object of our invention to provide such an apparatus in which brushes may be operated under relatively high temperatures 25 without damaging the bristles thereof.

` The manner of accomplishing the foregoing objects as well as further objects and-advantages will be made manifest in the following description taken in connectionv with the accompanying drawingsin which:

Fig. 1 is a diagrammatic longitudinal sectional view of a preferred embodiment of the apparatus of our invention, the plane onwhich said sectional viewv istaken being indicated by the line 35 lI-I of Fig. 3.` f y Fig. 2 is a side elevational view of that portion of the apparatus shown in Fig. 1 which embodies the furnace and control means therefor.

Fig. 3 is an enlarged transverse sectional view taken on the line 3-3 of Fig. 2 and illustrating the furnace and the means for mounting and driving the brush rollers'of the drier.A

Fig. 4 is an enlarged detail side elevational view taken in the direction of the arrow 4 in Fig. 3 and illustrating the solenoid damper control of the apparatus of vour invention.

Fig. 5 is a fragmentary horizontal sectional'l view taken on the line 5,-5 of Fig. 3 and illustrating the hot air damper and distributing bailles 50 of our invention.l l

' Fig. 6 is a fragmentary side elevational view Y taken in the direction ofy the arrow 5 of Fig. 3 and illustrating the'mechanism for driving the brush rollers and cleanout mechanism of the apparatus of our invention;

' Fig. 7 is a wiring diagram illustrating the electric safety control system of our invention.

Referring specifically to the drawings, the apparatus of our invention is there seen to bel .embodied in a drier i which includes a frame Il, a bed i2 formed of rotary brushes I3, a cleanout mechanism I4 for propelling rollable fruit F over the bed I2, a drive mechanism I for driving the rollers i3 of the bed l2 and also operating the cleanout mechanism I4, and an automatically controlled furnace unit i5.

The frame li includes similar side assemblies and 2|, the first of'these being referred to hereinafter as the idle side assembly and the second as the drive side assembly. Each of these assemblies has legs 22 and caps 23. Each of these caps has angle iron attaching ears 24 at its lower enel.y At their upper ends on the idle side of the drier these caps have pipe clamp bases 25a and, on the drive side, similar bases 25h.

Resting in the pipe clamp bases 25a. is a longitudinal frame pipe 25 which is held in place by idle pin mounting blocks 21 which rest on top of the pipe 25 and are secured rigidly in place by bolts 28 which unite these blocks with the clamp bases 25a. Other bolts 28 unite the blocks 21 with individual clamp caps 3l'l.` Each of the blocks 21 has an arm 35, these arms supporting a sheet metal side wall 36 of a housing 31. Each block 21 also provides a piurality'of supports 38 each of which has a bore in which an idle brush roller pivot pin 39 is adapted to be adjustably secured byl a set screw 40. The pins 39 extend through suitable apertures formed in the side wall 35.

Resting in the clamp bases 25h is a frame pipe which is held in place by gear housing blocks 46 which are secured by bolts 41 to the clamp bases 25h and to simple clamp caps 48. Each of the blocks 46 has an ear 50, the latter supporting a side wall 5I of the housing 31, and enclosing driven gears 52 which are mounted on individual roller drive shafts 53, and which extend through suitable openings in the pipe 45 to mesh with drive gears 54 provided on a square shaft 55 which extends throughout the length of the -pipe and is supported in suitable bearings provided therein. One of the shafts 53 in the unit 46 near the discharge end of the drier i0 extends outwardly through that housing unit and has provided thereon a sprocket 55, .the purpose of which will be made clear hereinafter.

'I'he main drive shaft 55 extends from o'ne end of the pipe 45 and has a sprocket and chain connection with a motor 51 by which this shaft is rotated. Each of the individual roller drive shafts I3 is mounted on the same axis as the corresponding idle pin 39, one of the rollers I3 being mounted between this shaft and pin with its opposite ends supported thereby so as to be driven by that shaft 53. All of the brush rollers I3 are thus rotated by the motor 51 in the same direction as indicated by arrows in Fig. 1.

'Ihe cleanout mechanism I4 is preferably substantially like that shown in U. S. Letters Patent to Hale Paxton No. 2,099,226, issued November 16, 1937, this mechanism being driven'by the sprocket 56 shown in Fig. 6. 'Ihis mechanism includes cleanout rods 68 which are supported at their opposite ends by endless chains 6I which travel along suitable tracks supported on the inner faces of the housing walls 36 and 5|, so that the upper flights of the chains 6I pass above the pins 39 and shafts 53 while the lower flights of these chains return to their starting point below these pins and shafts. As shown in the patent above referred to, the cleanout mechanism I4 includes an intermittent drive device 82 by which travel of the cleanout rods 88 is accomplished, each ofthe rods being shifted rapidly from above one of the brushes I8 .until it is above the next adjacent brusli and pausing for a second or two while located directly above each of the brushes. The purpose of the cleanout mechanism is to insure a positive flow of fruit through the drier |8.

The upper fiights of the chains 6| and the tracks guiding these are covered by aprons 63 provided on walls 36 and 5I, these aprons preventing contact of fruit F with the chain 6| while said fruit is resting on the brush rollers I3.

The housing 31 includes the .side walls 86 and 5|, the aprons 83 provided thereon and a oor 68 which covers the open space between the lower edges of these walls and is supported by angle iron cross members 69 which are bolted to the ears 24. The housing 31 also includes intake and discharge end walls 18 and 1| and intake and discharge transfer boards 12 and 13.

The furnace unit I6 includes a furnace 15 including a fire box 16 and a plurality of burners 11 `discharging into clay combustion pipes 18 and having control valves 19, which are supplied with gas through a manifold 83. Connected with a draft conduit 84 in the upper portion of the fire box 18 is a discharge adapter 85 of a small blower 86 which is driven by motor 81, this preferably being of about one-sixth horsepower. Discharge of the gases of combustion from the fire box 18 is accomplished through a goose neckl stack 88 which extends upwardly through the floor 68 into a hot air chamber 89 provided within this housing beneath the brush bed I2. The draft conduit 84 is kdivided into two Venturi nozzles 98 which curve upwardlywithin the goose neck stack 88 and terminate inside the mouth 9| of the stack.

The escape of heat from hot air chamber 89 is prevented by the provisionvof a layer of insulation 92 covering inner faces of those portions ofe the housing 31 surrounding that chamber. As shown in Fig. 1, the stack 88 discharges gases of combustion from the burners 11 and` air from the blower 86 into the chamber 89 in a horizontal direction, this hot air being spreadlaterally somewhat so askto ll the entire chamber 89 by baille plates 93.

'I'he mouth 9| of the stack 88, as shown in Figs. 1 and 3, is pointed directly towards the opposite end of the chamber 89 from that into which this mouth discharges hot air.

Pivotally mounted so as to have an upper, open position and a downward position in which it 'closes the mouth 8|, is a damper I8I, this damper being mounted on and controlled by a rod |82 whicn extends outwardly through -the wall 36 andl has an arm |84 xed on the outer 'end thereof, on the free end of which arm is provided a pin |88. Attached to this arm and to the wall 38 is a contractile spring |81 which continually urges the arm |84 in a direction tending to swing the damper |8| from open into closed position. Mounted upon the frame is a solenoid I I8 having an armature which is yieldably urged upwardly by a spring I|2. The upper end of the amature III connects to one end of a lever |I3 which is pivotally fulcrumed on the frame II and has a notch I|5 at its opposite end which notch engages the pin |85 and retains the damper I8I in open position when the armature I|| is drawn down, the latter being effected by the electrical energizing of the solenoid |I8.

The gas manifold 83 is supplied with gas through a pipe |28, this supply pipe having three control valves, I2I, |22 and |23, arranged serially therein. The control valve I2I is actuated by an adjustable thermostat |25 which extends into the hot air chamber 89 and increases or decreases the flow of gas to the furnace 88 so as to maintain the temperature in the chamber 89 at a pre-determined value. The valve |22 is controlled by a solenoid |38 which is connected in the electric circuit of the motor 51 so that if the supply of electricity for thatmotor should fail or the latter burn out, the valve |22 would automatically shut olf the supply of gas to the furnace 15. The valve |23 is actuated by a solenoid |3I which is connected in series with the electric motor 81, with a rheostat I 32 for controlling the speed of the latter, and with the solenoid II8. The solenoid |3| operates so that when said circuit is energized, the valve |23 is held open and the 'armature of the solenoid |I8 is held down against the action of the spring ||2 so that when the damper I8I is open so as to bring the pin |85 within the notch |I5 the pin is retained in this notch and the damper |8| is held open.

When this circuit fails, however, as by the electricity going off or by burning out of the motor 81, the valve |23 automatically closes thereby stopping all iiow of gas to the furnace 15. At the same time the solenoid 8 relaxes its hold on the armature III permitting the spring 2 rto lift this thereby freeing the pin |85 and allowing the spring |81 to immediately swing the damper I8|` downwardly in a position to close the mouth 9| of the furnace stack 88.

Operation The preferred manner of operating the drier I8 in carrying out the method of our invention is as follows:

'I'he electric circuits of the blower motor 81 and 0f the drive motor 51 are first energized to cause the .first ofthese motors to direct a blast of air through the draft conduit 84 and out of the Venturi nozzles 98 thereof and the other of these motors to rotate the rollers |3 and intermittently actuate the cleanout mechanism I4.

The energizing of the electric circuit of the motor 81 also energizes the solenoid ||8 thereby causing it to draw downwardly upon the armature III. As the damper |8| is always automatically closed when the drier I8 is shut down,

it is necessary now to swing the arm IM downwardly to engage the lever Il and rock this slightly permitting the pin |85 to come to rest in the notch where it will be retained by the constantl tension of the solenoid H0 on the lever III. This opens the damper |8| and permits the blasts of air from the Venturi nozzles 98 to be projected through the mouth 8| of the stack 88 into the hot air chamber 85.

By opening up any desired number of the valves `1li and lighting the burners 11 controlled by these valves, the clay combustion pipes 18 in which these burners are disposed are filled with blasts of flame from'these burners, thejgases of combustion from which flames are discharged from the right hand end of these pipes into the stack 88. These gases of combustion are of a very high temperature which of themselves would be sufiicient to burn the brushes I8 if allowed to rise upwardly thereagains't from the mouth 9| of `the stack. The blast of air produced by the blower 88, however, dilutes these gases of com bustion and gives these a velocity which carries the' diluted mixture of air and combustion gases from the right hand end oi' the hot air chamber 89 clear to the left hand end of this chamber adjacent the fruit receiving end of the drier.

The method of our invention, las broadly set forth in our copending application above referred to, embraces the vigorous brushing of the fruit for a substantial period of time in the presence of heated air which is caused by. virtue of its heated condition and at a rate produced thereby .to ilow over the fruit and the brush bristles em- In the apparatus ployed in brushing the same. disclosed in said copending application, a relatively deep flre box was provided beneath the brush bed employed for brushing the fruit, and hot air and gases of combustion were produced in this fire box by burners located in the bottom of this. The present invention represents an effort to carry out said method with a less expensive apparatus with whichequivalent conditions can be produced while at the same time giving a better opportunity for controlling these.

To supply the drier In with the necessary heat, the burners 11 of the furnace 15 are adapted to discharge into t'he stack 88 a mass of combustion f effect in heating the bristles and the fruit which is obtained at the right hand or discharge end of the drier. The regulation of the speed of the motor 81 by the rheostat |32, see Fig. 7, permits the application of a blast of air of just the right magnitude to the gases of combustion flowing through the mouth 8| of the stack 88 to give the above result.

Thus in the drier l0, it is possible to obtain, by proper choice of the number of burners 11 which are ignited, the extent to which the valves of these burners are opened, and the speed at which the motor 81 is run, to cause with an absolute minimum of heat losses, the maintenance of the optimum temperatures of the air adjacent the bristles of thebrushes and the fruit resting thereon throughout the length of the drier I8.

The thermostat |25 extends into the hot air chamber Il on the axis of the control valve I2l,

'as shown in Figs. 1 and 2, this thermostat lying constantly in the stream of hot4 air owing through the chamber 89. As this thermostat is adjustable, it canbe set to maintain a desired temperature in the air stream at this point. The adjustment of the. speed of the blower motor and the burners 11 of the furnace 15 are necessary to insure that a sufiicient volume of hot air is produced and that this is given a sufficient velocity to insure that the stream of air passing the thermostat |25 at the desired temperature is adequate to supply upwardly rising convection currents of hot air for the entire distance between the thermostat |25 and the fruit receiving end of the drier.

As described hereinabove, the damper |0| is controlled by the solenoid |||l so that this damper is automatically closed whenever the blower motor 81 fails. This automatic control is necessary to protect the brushes I3 located in the vicinity of the stack mouth 9| from destruction by the excessive heat of the combustion gases normally discharged upwardly through the stack into the' hot air .chamber 88.

Failure of the power circuit of the blower motor 81, however, also closes gas valve |23 by deenergizing the solenoid |3|. This shuts off the supply of gas to the furnace 15 so that the burners 11 are immediately extinguished. Thus, the furnace 15 will eventually cool down so that no damage will be done to the furnace by the closing of the stack by the damper Ilil.

In ordinary practice it is preferable that 'a minimum temperature of 135 degrees Fahrenheit be maintained in the air stream as this emerges from the mouth 8| of the furnace 15.

What we claim is:

l. In a drier for fresh whole fruit the cornbination of a relatively long and substantially horizontal bed of rotary brushes; means for continuously rotating said brushes to rotate and brush fruit resting thereupon; a housing for enclosing a relatively shallow chamber coextensive horizontally with said bed and disposed therebeneath, said housing so confining air in said chamber as to permit said air to escape therefrom in practically no other way than upwardly between and through said rotary brushes; and means for supplying a stream of hot air to one end of said chamber at a rate to compensate for loss of hot air from said chamber caused by convection currents carrying said air up through and between said brushes, and being, therefore, sufllcient to keep said chamber filled with said hot air despite said losses.

2. In a drier for fresh whole fruit the combination of: a relatively long bed of rotary brushes disposed transversely with the path of travel of said fruit through said drier; means for continuously rotating said brushes to rotate and brush fruit resting thereupon and to assist fruit in travelling from the receiving end to the discharge end of said drier; a housing for enclosing a relatively shallow chamber coextensive horizontally with said bed and disposed therebeneath, said housing so confining air in said chamber as to practically prevent the escape of said air from said chamber otherwise than upwardly between and through said transverse rotary brushes; and

means for supplying a stream of hot air to one air from said chamber caused by convection currents carrying said hot air up through and between said brushes, and being, therefore, sumcient to keep. said chamber fllled with hot air despite said losses.

3. In a drier for fresh whole fruit the combination of: a relatively long and substantially horizontal bed of rotary brushes; means for continuously rotating said brushes to rotate and brush fruit resting thereupon; a housing for enclosing a relatively shallow chamber coextensive horizontally with said bed and disposed therebeneath, said housing so confining air in said chamber as to permit said air to escape therefrom in practically no other way than vupwardly between and through said rotary brushes; and means for supplying a stream of hot air and directing saith chamber caused by convection currents carrying said air up through and vbetween said brushes, and being, therefore, sufficient to keep said chamber filled with said hot air despite said losses.

4. In a drier for fresh whole fruit the combination of: a relatively long bed of rotary brushes disposed transversely with the path of travel of l said fruit through said drier; means for continuously rotating said brushes to rotate and brush fruit resting thereupon and to assist fruit in travelling from the receiving end to thedischarge end of said drier; a housing for enclosing a relatively shallow chamber coextensive horizontally with said bed and disposed therebeneath, said housing so confining air in said chamber as to practically prevent the escape of said airfrom said chamber otherwise than upwardly between and through said transverse rotary brushes; and

means for supplying a stream of hot air to one.

end of said chamber beneath the discharge end of said drier, said stream being of such a volume and rate of flow as to compensate for the losses of hot air from said chamber caused by convection currents carrying said hot air up through and between said brushes, and being, therefore, suilicient to keep said chamber filled with hot air despite said losses, said stream of hot air rbeing directed into said chamber substantially horizontally and pointed in a direction towards, the receiving end ofthe drier.

5. .In a drier for fresh whole fruit the combination of a substantially horizontal bed of rotary.

brush bed; blower means for directing a blast of airinto said stack, the air so introduced diluting the combustion gases in said stack, reducing the 'temperature thereof and propelling said combustion gases into said chamber; anddamper means automatically4 closing the dischargemouth of the l aforesaid stack when said blower ceases to operate. I

6. A method of removing surface moisture from whole fresh fruit which comprises subjecting said fruit to a vigorous brushing action .within a certain area in a. given substantiallyhorizontal plane, then propelling a current of hot air substantially horizontallyfrom one edge of said area and beneath said plane towards an opposite edge of said area so as to provide quantities of said hot air throughout the space immediately below said brushing area, and permitting said hot air to rise upwardly under the impulse of convection currents pro-` duced by buoyancy of said air resulting from its elevatedv temperature so that said hot air flows over the surface of said fruit and the bristles employed in said brushing action.

7. A method of removing surface moisture from whole fresh fruit which comprises subjecting said fruit to a vigorous brushing action within a certain area in a given substantially horizontal plane, confining a space directly beneath said-area and propelling into said space adjacent one edge of said area, a stream of hot air just suilicient in volume and velocity to carry said stream to the opposite edge of said area andreplenish losses from said stream caused by convection currents of said hot air rising from said stream to flow over the surfaces of said fruit and of the bristles 

